The present invention relates to shrink packaging, and more particularly to a shrink package produced from a traY and a thermoformable, shrinkable material.
Many applications for the packaging of food and non-food products, particularly meat products, involve the use of a thermoforming system in which a heat formable material is formed into a cavity and thereafter a product is inserted into the thus formed cavity.
In other types of packaging, a preformed tray is loaded with a product such as a meat product, and thereafter overwrapped by various means including hand wrapping and machine wrapping, to create a complete package.
One problem that has been encountered is how to produce a controlled atmosphere package with low residual oxygen in a tray with a tight lid or overwrap. This problem is especiallY pronounced in the case of high profile products that extend above the edge of the tray.
It has now been discovered that a thermoformable web made from a film or laminate can be deep drawn to form a pocket or cavity. A product such as a meat product can be inserted into the cavity. A tray maY then be sealed in an upside-down arrangement to the top of the thermoformed web in a vacuum chamber with optional gas flushing capabilities. The bottom web is made from a material having some shrinkability even after the thermoforming process. Upon shrinking the bottom web, a tight package with or without the controlled gas atmosphere can be produced.
Both the tray and the bottom web can optionally include a barrier layer or a barrier film applied as a separate step.